# math_demo.py
# f"{a} + {b}" 叫 f-string，类似 JS 的模板字符串 `${a} + ${b}` 
a = 5
b = 3
sum = a + b
print(sum)
print(f"{a}")
print(f"{a} + {b} = {sum}")
diff = a - b
print(f"{a} - {b} = {diff}")
prod = a * b
print(f"{a} * {b} = {prod}")
quot = a / b
print(f"{a} / {b} = {quot}")